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Conduit

Prefab children

ScreenChild and LabelLine are the JSON-authorable children of a prefab’s Screen and Label elements. They’re flat records — every variant uses the same shape and a kind field picks which fields matter at render time — kept that way so the JSON stays lightweight and agent-readable, and so a prefab editor can add a new row without changing the codec layout.

When to use it

Section titled “When to use it”
  • You’re authoring a prefab that includes an in-world panel (lobby info screen, leaderboard).
  • You’re authoring a multi-row floating label (hub hologram, podium sign).
  • You’re writing a tool that emits prefab JSON and needs the child schemas.

API

Section titled “API”
package me.zlex.conduit.prefab;


public record ScreenChild(Kind kind, Region region, String text, String buttonId) {
    public enum Kind { TITLE, BODY, CAPTION, BUTTON, PANEL, DIVIDER }


    public static final Codec<Kind> KIND_CODEC;
    public static final Codec<ScreenChild> CODEC;
}


public record LabelLine(String text, WorldLabel.RowKind kind, int argbColor) {
    public static final MapCodec<LabelLine> MAP_CODEC;
    public static final Codec<LabelLine> CODEC;
}

ScreenChild.Kind maps to widget kinds at render time: TITLE/BODY/CAPTION → LabelWidget, BUTTON → ActionWidget(PRIMARY), PANEL → PanelWidget, DIVIDER → DividerWidget.

Example

Section titled “Example”

A label and screen authored inside a prefab JSON:

{
  "elements": [
    {
      "type": "label",
      "anchor": "header",
      "yaw": 0,
      "argbColor": 4294967295,
      "lines": [
        { "text": "SPRINT RACE", "kind": "header",    "color": 4294943232 },
        { "text": "Solo",         "kind": "subheader", "color": 4286611584 },
        { "text": "Run to win.",  "kind": "text",      "color": 4291611852 }
      ]
    },
    {
      "type": "screen",
      "anchor": "panel",
      "yaw": 90,
      "width": 4.5, "height": 4.0,
      "children": [
        { "kind": "panel",   "region": { "x": 0,    "y": 0,    "w": 1,    "h": 1    } },
        { "kind": "title",   "region": { "x": 0.05, "y": 0.04, "w": 0.9,  "h": 0.1  }, "text": "Lobby" },
        { "kind": "divider", "region": { "x": 0.05, "y": 0.16, "w": 0.9,  "h": 0.01 } },
        { "kind": "body",    "region": { "x": 0.06, "y": 0.20, "w": 0.88, "h": 0.04 }, "text": "Walk in to ready up" },
        { "kind": "button",  "region": { "x": 0.32, "y": 0.84, "w": 0.36, "h": 0.10 }, "text": "START", "button": "start" }
      ]
    }
  ]
}

Notes

Section titled “Notes”
  • For ScreenChild, text is the visible string for label-like kinds and the button label for BUTTON. buttonId is the click handler key — only meaningful for BUTTON.
  • LabelLine.color is an ARGB integer. The MapCodec keeps each line compact; the prefab editor can edit one row at a time without rewriting the whole element.
  • Both record types are deliberately flat — adding a new variant means a new Kind value, not a new sealed class.
Section titled “Related”